Product Literature

Marvair CommStat4 Modbus Interface I-O Manual (Rev.5) (pdf - 9736 KB)
CommStat 4 Product Data Sheet & Installation Manual (Rev. 23) (pdf - 2073 KB)

CommStat 4 HVAC Controller CommStat4-Silo

Our most comprehensive HVAC controller for air conditioners or heat pumps in a telecom shelter or enclosure.

A single CommStat 4 will control two redundant air conditioners or heat pumps, but has the capability to be daisy chained with a second CommStat 4 unit for controlling up to four air conditioners or heat pumps in a shelter. The CommStat 4 has seven outputs for remote alarms or notification.

A unique Marvair feature, the Comfort button, allows a service tech to easily change the temperature to provide a comfortable working environment. After 90 minutes, the temperature set points automatically revert back to the programmed temperature set points. The CommStat 4 also stores the last 10 ten faults that were registered. 

Specifications / Features:

  • Thermostat Range:
    • Cooling: 65° - 95°F (18° - 35°C) in 1° increments.
    • Heating: 50° - 80°F (10° - 27°C) in 1° increments.
  • Differential:
    • Adjustable ON-OFF differential for both Stage 1 and Stage 2
    • Adjustable changeover differential between heating and cooling.
  • Control Voltage: 24 VAC
    CommStat 4 Inputs
    • Input power
    • Modem Connection
    • Control voltage
    • Line Voltage
    • Temperature Sensors
    • Smoke Detector
    • Hydrogen Detector
    • Generator Relay
    • Economizer Mode Status Monitoring
    • Lockout Relay
    • Aux 1/ Aux 2
    Ease of Installation
    • Wiring connection insensitive to phasing of the HVAC units.
    • Easy terminal connections for thermostat wire.
    • Remote temperature sensors insure accurate temperature readings.
    Lead/Lag Operation
    User selectable changeover from 1/2 to 7 days in 1/2 increments. If the lead unit loses power, the lag unit automatically becomes the lead unit with all the set points of the lead unit. A lead swap button alternates the lead and lag unit, allowing service techs to easily check the operation of each unit.

    Dry contacts can be used for remote alarm or notification. Relays can be wired Normally Open (NO) or Normally Closed (NC).
    • High (Line) Voltage
    • Low (Control) Voltage
    • Lockout
    • Low Building Temperature
    • Smoke alarm
    • First Stage High Building Temperature
    • Second Stage High Building Temperature
    • Aux 1 & Aux 2

    For detailed specifications, performance, and efficiency information, download the Product Data Sheet from the document list on this page.